Calculating device.



FREDERIK JOHAN CONSTANTUN BARON VAN HARDINBROEK VAN AMMERSTOL.

CALCULATIIJG DEVICE. APPLICATION FILED DEC. a, I9I4.

Patented Deo. 7, 1915.

3 SHEETS-SHEET l.

FREDERIK JOHAN CONSTANTUN BARON VAN HARDENBROEK VAN AMMERSTOL. CALCULATING DEVICE.

APPLICATION FILED DEC. 3. 1914. 1,162,828 y Patented Dec. 7, 1915.

3 SHEETS-SHEET 2.

FREDERIK JOAHAN CONSTANTIJN BARON VAN HARDENBHOEK VAN AMMERSTOL.

CALCULATING DEVICE. APPLICATION FILED 050.3. I9I4.

1,162,828. Patented Dec. 7, 1915.

3 SHEETS-SHEET 3.

I NN ENTE I1@ UNITED SATB@ FREDERIK JOHAN CONSTANTIJN BARON' VAN HARDENBOEK VAN MMERS'EOL, OF UBBERGEN, NETHEIt/LLNDS.`

cancunafrine nnvrcn.

Application filed @eeen-iter S, 191e.

To all whom it may concern.'

Be it known Ithat I, Fiinnnnin JOHAN CoNsTANTIJN BARON VAN HAnDnNBRoEK van AarMnns'roL, secretary of the army, a subject of the Queen of the Netherlands, residing at Ubbergen, Netherlands, have invented certain new and useful Improvementsin Calculating Devices; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same. y

Myv invention relatesto calculating devices for determining results involving elapsed time as one factor, such, for instance, as the number of days between two dates, or the interest at a certain annual rate payable on one dollar for the time between two definite dates; and the object of the invention is to provide a device of this kind wherein the result maybe read directly at one of the dates when the other date is registered with an index. In the preferred form of construction, the results are arranged on a fixed table, and the dates are arranged on a transparent slide movable-over the table to bring any date into registry with an index on the table, the slide being carried in a guiding structure which is likewise applicable to other forms of calculating devices.

In the accompanying drawings illustrating this preferred form of construction in application to a calculating device for determining the number of days between two dates, as an example, Figure 1 is a plan view of the calculating device; Figs. 2 and 3 are sections on lines 2 2 and 3"-3 of Fig. l, respectively; Fig. 4 represents the results arranged on the xed table; and Fig. 5 represents the dates arranged on the movable slide.

A rectangular plate a of wood, slate or other suitable material is fastened Iwithin a wooden inclosing frame Z) which projects outwardly of both faces thereof and has longitudinally extending guiding grooves on theinner surface ofits top and bottom members along each face of the plate. There is a rectangular frame c along each face of the plate a, and each frame has longitudinally extending tongues iitted in the grooves of the frame b. Each frame c is provided alongthe inner surface of its Side Specication of 'Letters Patent. PQM-@@Hqgd BQQO E', 1239115 Serial No. 375,375.

members with guiding grooves in which the .frame CZ slides transversely. Each frame ci rows, the values being inserted at one sideof the areas of intersection of the columns and rows. The plate a is provided with a table divided into a plurality of columns and rows, the results being inserted at the other side of the areas of intersection thereof, and it is also provided with an index positioned centrally of the table, as shown, that is, in the area of intersection of one of the intermediate columns with one of the intermediate rows. The guiding structure is such that any value on the slide may be brought overtbe indeX of the table by Inoving the frame c longitudinally in the frame b and moving the frame d transversely in the frame c. IVhen any value on the slide is so registered, then the intersecting areas on the slide lie directly over the intersecting areas on the table, and the values on the slide are contiguous to the results on the table, so that the result of the calculation is visible through the slide at the immediate right of the determining value on the slide.

The slide is divided into twelve columns corresponding to the months of the year and into rows corresponding to the days of the month. The values in each column represent the consecutive days of the respective month and start in such mannerthat a constant interval of days exists between the two values of the same row in two adiacent which is adapted for 365 days, the interval of days between sidewise adjacent values is 30, the value in one column starting one row lower than in the preceding column if the preceding month contains 31 days, and starting in the same row if the preceding month consists of 30 days. The first day in March is represented in the second row above the first day of February, since, in a year of 365 days, February contains but 28 days. Thus the slide of Fig. 5 has the varied -arrangement shown and contains 36 rows.

The table of results shown in Fig. 4 is adapted for the calculation of the interval of days between any two definite dates on the slide of Fig. 5, and preferably the results are repeated as shown in order that a single setting of the slide suiiices even if the two dates are in successive years vor are near the beginning and end of any two months. rihus the table. of results has 23 columns, equal to one less than double the number ot columns on the slide, and Tl rows, likewise equal to one less than double the number ot rows on the slide, the valuesv in the same row of adjacent columns having a constant dit`- ference. ot 30, equal to the interval ot' days between dates on the slide lying in the same row of adjacent columns-` 'lhe index, which is preferably colored or otherwise rendered distinctive, is placer to the lett ot the result Bvvhich forms the end of the first series of differences on the table, and also 'forms the Zero point oi the second series of ditl'erences; and inasmuch as tais table is adapted for a year ot 365 days, whereas Vthe ditierence between sidewise adjacent results is 30, the results in the second series sets tive rows lower than the corresponding results in the first series. rl`he results are continued sutiiciently above and below the row containing the index that every dateon the slide is in registry with a result on the table, no matter what date on the slide is registered with the index.

The method ot using the device having the values and results shown in ligs. el and 5 is as tollows-Te determine the interval of days between any two dates of the same year, as for example April 5th and duly 16th, the number 5 in the column of April is brought over the index, and 102 is read on the table at the right of number lll in the column of July on thegslide. Similarly, to tind the interval oit' days between November ith ot one year and February 3rd of the next year, the number 7 of the column of `November is registered with the index, and 8S is read from the iirst series of results at the right ot' number 3 in the column ot li`ebruary rl`he device may also 'be used to determine the date occurring at a delinite number ot days following any other date, by registering the given date with the index and reading the second date on the slide at the lett of the given number of days on the table ot' results.

From the foregoing it will be understood that the results are determined by a single ksetting involving but a small amount of movement oi the slide in any case. lso the gures on the slide and table stand upright and lie side by side when the slide is positioned for any problem.

instead of adapting the table for the de-y termination ot' the interval of days between two definite dates, the results may represent any determination in which the inter val of days on the slide is a factor. For instance, the results may represent at a given annual rate, the interest per dollar `from l to 305 days. rlhe second `tace of the table a. may contain a table of results of this kind, or it may be arranged Vtor determining the` number otl days between two dates when the year is divided into twelve months otl thirty days each, ln the scribed. a transparent slide bearing a single' series oi' unrepeated dates arranged in twelve columns corresponding to the months otl the year and in rows corresponding to the days ot' the month, a tixed table. bearing a plurality ot series oi' repeated results arranged in columns and rows so as to register individually with the dates on the slide and having an index intermediate of said series, and guiding means whereby the slide is movable over the fixed 'table to bring any date on the slide into registry with the index. y

` 2. ln a calculating device of the kind described, a movable transparent slide divided into twelve columns corresponding to the months ot the year and into rows corresponding to 'the days or' the months so as to form a plurality ot' intersecting areas, a `fixed table divided into columns and rows so as to form a plurality ot intersecting areas like those ot' the slide, an index on the table positioned in such manner that when any intersect-ing area of the slide is registered with it, all the intersecting areas of the slide register respectively with the intersecting areas of the table, a series of dates arranged within the intersecting areas ot' the slide to one side thereof, and a series of results arranged within the intersecting areas oi' the table to the other side thereof, whereby when any one date is registered with the index a vresult appears through the slide directly at the side ot every date.

3. ln a calculating device ot' the kind described, 'a movable slide bearing dates arranged in twelve columns corresponding t0 the months o1t` the year and in rows corresponding to the days of the month, a fixed table having an index and bearing results arranged in columns and rows so as to register individually with the dates on the slide when theslide is positioned relatively to the index, the results in the same row of adjacent columns otl the lixed table having a constant diti'erencmand the dates in the same row of adjacent columns ot' the slide representing an interval oit thirty days.

'-l. ln a calculating device of the kind described, a slide bearing dates arranged in rows Jforming at least twelve columns representing the months ol' the year, wherein lil@ the dates in the same row of adjacent columns represent a constant interval of days,

and a xed table bearing results arranged in at least twenty-three columns and in a .number of rows equal as a minimum to one lless than double the number of rows on the slide wherein the results in the same row of adjacent columns have a constant difference, said table having an index positioned' at the intersection of one of the intermediate columns and one of the intermediate rows,

FREDERIK JOHAN CONSTANTIJN BARON VAN HARDENBROEK VAN MMERSTOL. l

Witnesses: y W. R. ,ATKINsoN, EUGENE NABEL. 

